Antibodies or antibody fragments, reduced and lyophilized for use in preparing instant, one-step Tc-99m radiopharmaceuticals, can also be labeled with Cu-67. The Cu-67, as Cu(II) in a ph 5.6 buffer, is simply added to the antibody to generate the Cu-67-labeled antibody. The purpose of this project is to determine the parameters of this reaction and the purity, stability, and immuno-reactivity of the resultant radiolabeled product. During Phase II, direct labeling using Cu-67andother radiometals will be evaluated and the products will be tested in animal models compared to the same antibody labeled with Tc-99m. Ultimately, radiolabeled antibodies will be made for therapy and PET imaging studies. This approach permits the same antibody, using the same labeling chemistry, to be labeled with several different radio metals, including Tc-99m and Cu-67. Phase III studies will include human trials of validated and clinically relevant diagnostic or therapeutic radiopharmaceuticals.